Internal-combustion engine



Jam. 5 192e. 1,568,342

' A. D. MaGFARLANE INTERNAL COMBUSTION ENGINE Filed April 28, 1924 nvemko'o Patented Jan. 5, 1926.

. IUNITED STATES ARTHUR D. MAGFARLANE, 0F SEATTLE, WASHINGTON.

INTERNAL-COMBUSTION ENGINE.

Application led April 28, 1924. Serial N0. 709,578.

To all whom 'it may concern:

Be it known that I, ARTHUR D. MACFAR- LANE, a citizen of the United States, residing at Seattle, in the county of King and State of Washington, have invented certain new and useful Improvements in Internal-Combustion Engines, of which the following is a specification.

This invention relates to internal combustion engines, and it consists in the novel features hereinafter described and claimed.

An object of the invention is to provide an engine of the character stated, which is light' in weight, and which may develop maximum power.

A further object of the -invention is to provide in such an engine, means whereby the products of combustion are completely expelled from the engine cylinder at the ends of the power stroke of4 the piston, and means whereby premature explosions in the' crank casing are avoided.

With the above objects in View, the strucr ture includes a cylinder having a-valve con# trolled inlet port provided in the' vicinity of one end thereof, and an exhaust port prol ed in the side of the vided at points between the ends thereof. A main piston is slidably mounted in the cylinder, and may be operatively connected .with the valve on the inlet port, in any approved or usual manner. A displacer piston is slidably mounted in the cylinder, for movement across the valve controlled inlet port, but its path of movement within the cylinder is limited by the first mentioned piston to align approximately at the exhaust part of the cylinder.

In the accompanying drawing,

Figure 1 is a sectlonal view of the engine, showlng the positions of the parts whenithe main piston is at the ends of the power stroke, in the cylinder.

Figure 2 is a similar view, showing the relative positions of the arts, when the' main piston is at the end ci) its compression stroke, in the cylinder.

The engine comprises a cylinder 1 having an inlet port 2, at one end, the passageway through which is controlled by a valve 3, in a usual manner. A spark plug 4 is mountcylinder 1 just beyond,1 the inner end of the inlet port 2. The cylinder 1 is provided, at a point between its ends with one or more exhaust ports 5. One end of the cylinder 1 is closed by a head 6, having a central tubular guide 7. A stem 8, is slidably mounted in the guide 7, and a spring 9 vis interposed between the outer end of the stem 8 and the outer end of the guide 7, and is held within the guide. A displacer piston head is slidably mounted in the cylinder 1 and` is carried by the stem 8. A main piston 11 is slidably mounted in the cylinder 1, in a usual manner.

By the intake stroke of the piston 11, the mixture is drawn into the upper portion of the cylinder l, through -the inlet port 2 thereof,.and past the valve 3. As the piston 11 moves away from the head 6, the piston 1U. follows the said piston 11, and when the piston 10 passes over the port 2, the mixture is drawn into thecylinder 1 between the piston 10 and the head 6. When the piston 11 moves toward the head 6, it first encounters the piston 10, and moves the said piston toward the head 6, against the spring 7. At the same time, the valve 3 is moved to a closed position over the port 2. Thus, the

mixture is trapped. in the upper portion of the cylinder 1, and is compressed by the pistons 10 and 11. When the piston 11 arrives at the'upper end of its stroke, the compressed mixture passes around the piston 10, and enters the space between the pistons 10 and 11, as shown in Figure 2. At this4 time, the mixture is fired by the spark plug 4, and the expanding gases move the piston `11, in the lcylinder 1 beyond the exhaust ports 5, thus permitting the products of combustion to escape from the cylinder 1. At the same time, the tension of the spring 7 comes into play, and the piston 10 is moved toward the exhaust port 5 in the' cylinder 1, and the products of combustion are driven out of the cylinder 1, through the exhaust port 5. Having described lthe invention, what is claimed is:

An'internal combustion engine including a cylinder provided at one end in its side wall with a transversely extending recess having a valve controlled inlet port, land at' a point between its ends with an exhaust port, a head on said end of the cylinder provided with an 'outwardly extending hollow guide. a piston mounted for movement in the cylinder and adapted to cover and' uncover the exhaust port, a displacer piston mounted in the cylinder at the end adjacent the head and adapted to move across the intake port in a path of movement. which terminates short of the exhaust port, a stem extending from the d isplacer piston into the hollow guide, arsprlng impinging against i the outer end of the hollow guide and the end of the stem, and a mixture ignition means disposedV through the head and ex-Y tending into the recess to function between the intake port and the path of movement Yof the dsplacer piston. 10

In testimony whereof I ax myZ signuture.

ARTHUR D MACFARLANE. 

